Luna 36v charger and Focus Jam2


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2:41 PM
Sep 11, 2020
Does anyone have any experience with the 36v Luna charger used for a Focus Jam2? It uses the xt60 connector and I'm not positive that this will mate up with the Jam2 although they look to be the same pitch. There are also two extra small pins in the wiring going from the charger to the bike. I'm guessing that they might have to be closed to tell the bike the polarity is correct before it will start charging.

I'm interested because it can charge at a slower rate to help extend battery life and it can also charge to 80% which can also greatly extend battery life. I don't always want to charge at 4.5 amps and currently only charge to 100% the day of my ride but it's tough to estimate where 80% is in the charge cycle. I'm probably going to not always charge to 100% either. If I have 60% left, which is often the case after my rides I might not charge at all for a follow up short ride of say 15 miles. It's all about making an inaccessible, expensive battery last a bit longer for me. thanks
First of all Luna's charger success rate is not all that great to begin with.

Second is that Shimano, as well as Bosch etc. and their proprietary systems, use CanBus communication protocols that only allow their batteries to play nicely with their chargers. So even if you could adapt the correct plug to the XT90 of the Luna charger it wouldn't work to charge the battery and may in fact lead to some fireworks as per the E6000 charger manual:

E6000 charger manual.png

The stock charger is probably doing as good a job of charging your battery as can be done due to the aforementioned protocols anyway.
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This is not a stock Shimano battery or charger. It does charge pretty fast, which does shorten the life of li-Ion batteries more than a slow charge. The battery is proprietary and heavily encapsulated. The motor must be removed to replace it and while I can do that I've heard it's a wiring mess probably not rebuildable by anyone in the USA. And Focus parts might not be readily available in the future since they are no longer selling in the USA. Making the battery last as long as possible was my goal. I have turned all assist levels down because of this and fitness reasons which will help with that.

Focus does also have a special magnetic connector which probably makes any other charger a moot point as well. No I wouldn't try to adapt a connector without completely understand the circuits involved and that info just isn't available. Looks like I'll have to cross this bridge when the battery finally dies in the future. It's why removable Shimano batteries make more sense, like the Canyon for instance.
THANK YOU! I ran across a pretty amazing sounding deal on a 2018 Jam 2 29er (base model) still new on showroom floor (2 yrs old i know....) for $4000 Canadian ($2800 USD) was really considering buying it but knowing they pulled out of N.A. market i know there could be issues. I don't want anything to do with focus ebikes now. too bad, the reviews were really great.
That's a pretty good deal. I bought my Jam2 carbon 2018 a year ago and love it. Keep in mind that many of the parts are generic and the warranty still seems to be honored if you buy it from a dealer. I've had my rear wheel replaced and the frame (decal cracking) on warranty. I did have to do the labor on the frame swap but wanted to learn anyway. I've been really happy with the bike and its unique light nature too and have upgraded many things like cassette, shifter, bars, tires, wheel set, brakes and now the rear shock too. You can spend a lot more for a new bike of course but I think you'll find that for a first ebike it's really is a nice bike and new you will never get a bike for much less than $4-5000.
been looking on pinkbike, could get a lightly used commencal or trek for similar price and then i wouldnt have to worrry about parts availability for a very long the extra battery is a must for all day epics on the focal which i would intend to do occasionally, ant that's around another $1000 me its just not worth the risk with that proprietary battery. Glad you are enjoying yours, i'm sure its a fun bike no question there.
Yes someday, maybe 6 years, I'll need a new battery and will look into re-building mine if I still have the bike. And the smaller battery does encourage you to get a good workout by conserving power. I easily get 20-30 mile rides right now with room to spare. A used Specialized might be a better choice if you can find one. I only say that because I think the Brose motor is the best motor out there having ridden one.
You are right about that.
All they do, is buy generic product and slap their logo on it, they might make a slight change, a voltage display on the charger for example, whether thats done at the factory oversea's or in house who knows.

If the OP has a proprietary ebike, thats not good because you need to buy their charger. That is why there are two extra pins on the connector. You will be spending quite a bit of money buying the proprietary charger to go with your proprietary battery on your proprietary ebike. But for $4k, you can afford that, and a spare battery will be expensive too. Th

I have this charger

Creme de la creme
Solder in whatever connector you want or get Grintech to do it for you. Wont work with proprietary ebikes though.

The Focus Jam 2 sure does look sleek, 95% of the people on the pathway would have no clue its electric. Just too bad of its power levels. Does the UK market sell only 250W store ebikes, means Trek needs a 750W and a 250W, probably just the controller or different motors too. That'd be the info to find online. Interesting, searching it is.